The present invention relates generally to seals for an ink jet ink delivery system. More particularly, the present invention relates to a fluid interconnect seal for a modular ink jet ink delivery system.
A typical ink jet printer has a print head mounted to a carriage that is moved back and forth over a print media, such as paper. As the print head passes over appropriate locations on the printing surface, a control system selectively activates the print head to eject, or jet, ink drops onto the print media to form images and text characters.
To work properly, such printers must have a reliable supply of ink for the print head. One type of ink jet printer makes use a disposable ink pen that can be mounted to the carriage. Such an ink pen typically includes, in addition to the print head, a reservoir containing a supply of ink. The ink pen also typically includes pressure regulating mechanisms to maintain the ink supply at an appropriate pressure for use by the print head. When the ink supply is exhausted, the ink pen is disposed of and a new ink pen is installed.
Other types of ink jet printers make use of ink container portions that are separately replaceable from a print head portion. For this type of printing system the print head portion can include a pressure regulating mechanism to maintain proper operating pressure. The ink container portion may be mounted away from the carriage or mounted on the carriage. In either case, it is very important that the replaceable ink container and printer be capable of establishing a reliable fluid connection therebetween. This fluid interconnection should be capable of repeated disconnects and reconnects as the ink container is removed and reinstalled. For the case of ink delivery systems where differential pressure exists between ink passages and atmosphere the fluid interconnect should be robust enough to prevent leakage under normal operating pressures (positive or negative with respect to atmosphere) as well as under various environmental conditions the printer and ink containers are specified to experience either operating or non-operating.
Such an ink jet ink delivery system, also referred to as an IDS, often employs modular designs which frequently contain separate user-replaceable components for the ink supply cartridges and for the print head cartridges. In some designs an intermediate manifold or tubing system is used to transport ink from the ink supply cartridge to a print head cartridge.
Previous fluid interconnect designs have incorporated a single annular compliant face seal around each foam/screen fluid interconnect interface where the manifold connects to the print head cartridge. These seals may be subject to leaks (primarily air leaks). These leaks may especially occur if foreign materials or defects are present at the sealing interface. Air leaks at these interfaces may allow volatile components to evaporate from the ink or even allow the ink within the ink delivery system to dry out completely. Over extended printer usage, a small air leak can allow the print head cartridge to fill with air (as air replaces the ink the print cartridge is attempting to draw). This can cause the print head to deprime and prevent further printing.
One aspect of the present invention provides for a modular ink jet ink delivery system comprising a print manifold including a passageway therethrough for the transfer of ink and a pen tower removably and operatively engageable with the manifold. The pen tower includes a central passageway for receiving and transferring ink from the manifold. A retainer member is operatively connected to the manifold. A first sealing member is operatively connected to the pen tower and forms a first seal with the retainer member. A second sealing member is operatively connected to the retainer member and forms a second seal with the pen tower such that when the pen tower and the manifold are operatively engaged with each other, a redundantly sealed passageway is formed for the transfer of ink from the manifold to the pen tower.
Another aspect of the invention provides for an ink delivery system comprising an ink reservoir, a manifold assembly including a passageway for receiving and transferring ink from the ink reservoir, and a pen tower removably and operatively engageable with the manifold. A first sealing member is operatively connected to the manifold assembly and forms a first seal with the pen tower when the pen tower is operatively engaged to the manifold assembly A second sealing member is operatively connected to the pen tower and forms a second seal with the manifold assembly when the pen tower is operatively engaged to the manifold assembly.
Another aspect of the present invention provides for a modular ink jet delivery system comprising a manifold including a passageway therethrough for the passage of ink and a pen tower removably and operatively engageable with the manifold, the pen tower including a passageway for receiving and transferring ink from the manifold. A retainer member is fixedly connected to the manifold, and first sealing means are operatively connected to the retainer member. The first sealing means form a seal with the pen tower when the pen tower is operatively engaged with the manifold. Second sealing means are operatively connected to the pen tower. The second sealing means form a second seal with the retainer member when the pen tower is operatively engaged with the manifold, providing for redundant seals along the ink passageway.